1. Field of the Invention
The present invention relates to a trimming method and a trimmer for bonding a strip protection film to one of the front and rear surfaces of a silicon wafer and then cutting this protection film to have a shape along the outer shape of the silicon wafer.
2. Description of the Prior Art
There are known hitherto, in a method for manufacturing a semiconductor device for an IC, LSI or an ultra LSI, the step of boding a protection film to the surface of a silicon wafer and protecting the silicon wafer, and the step of cutting and polishing the rear surface of the silicon wafer obtained in the former step and making a finally obtained semiconductor device to have a predetermined thickness. In the former step, as described in Japanese Patent Unexamined Application Publication No. 10-32179, a strip protection film is temporarily bonded onto a silicon wafer and then a part of the protection film which excessively extends outward of the outer periphery of the silicon wafer is cut off, i.e., so-called trimming is conducted.
However, following the recent higher integration of electronic equipment, demand for making semiconductor devices used in the equipment small in size and light in weight becomes greater and the thickness of the protection film is necessary to be decreased. For example, it is demanded that the thickness of a protection film which is conventionally, normally about 100 xcexcm be decreased to about 15 xcexcm. As a result, if the thinner protection film is trimmed even by a laser beam, the film cannot smoothly cut off. Even if the protection film can be cut off, the cut end face of the film cannot be made neat. Thus, a problem that the quality of a semiconductor device itself or the later steps of the manufacturing process of the semiconductor device are adversely influenced and the like appear.
The inventor of the present invention investigated causes for the problems and found the following facts. If the thickness of the protection film decreases to a certain degree, then it becomes difficult to cut off the protection film itself, the cut end of the film is contracted by heat generated by a laser beam and the cut end face of the trimmed protection film cannot be made neat. Taking them into consideration, the inventor of the present invention could eventually complete the present invention.
Therefore, it is an object of the present invention to provide a silicon wafer protection film trimming method capable of ensuring trimming a protection film which protects a silicon wafer and making the cut end face of the trimmed protection film neat, and to provide a trimmer optimum for realizing this trimming method.
The invention will now be described following.
The trimming method according to the present invention exhibits excellent advantages in that it is possible to ensure trimming a protection film which protects a silicon wafer and the cut end face of the protection film thus trimmed can be made neat.
The trimmer according to the present invention exhibits excellent advantages in that it is possible to ensure trimming a protection film which protects a silicon wafer and the cut end face of the protection film thus trimmed can be made neat.